The age at which alcohol consumption by young adults begins is reported to be ever decreasing. Recent surveys indicate that over 10 percent of 13-year-olds use alcohol and about 70 percent of high schoolers consume alcohol more than once per month. Of these individuals, nearly one- third report binge drinking (defined as consuming more than 5 drinks per occasion) on a weekly basis. In light of these astonishing statistics, our lack of understanding about the underlying causes of adolescent- onset drinking is surprising as well as disturbing. The largest amount of data on this topic has come from studies using selectively-bred strains of rodents showing a clear genetic determinant of alcoholism. However, it is also recognized that genetics alone cannot account for the prevalence of alcohol abuse. Experiential factors must also act, either alone or in concert with genetic predispositions. Due to the early age of onset of alcohol consumption patterns, it is likely that experiences with alcohol occurring very early in life contribute to later acceptance of this drug. There are many ways through which human infants can experience the taste/odor cues of alcohol associated with highly positive social contexts. For example, respired alcohol odor can be detected from conspecifics. Direct exposure to ethanol can also occur through the ingestion of breast milk obtained from an alcohol- imbibing mother. Peak concentrations of alcohol are found in breast milk within 1 hour after maternal ingestion, and alcohol levels in milk are equivalent to maternal blood-alcohol levels. The specific aims of this proposal are to examine these types of early experience and how they might contribute to a young organism's learning positive associations between alcohol and affective context. Our studies will focus on using the developing rat as a model system. The first type of experience with alcohol that will be studied is exposure through the ingestion of alcohol-adulterated milk during a simulated nursing bout. Long-term exposure to this drug during nursing could have serious consequences for later voluntary intake of alcohol. A second type of experience that could lead to modified alcohol acceptance patterns is through social interactions with a conspecific that has just ingested alcohol. It is anticipated that the detection of respired alcohol in this situation will increase later alcohol intake. Both types of early experience with the odor and taste of ethanol could have a substantial and possibly long-term impact on an animal's willingness to ingest alcohol.